Carbon pile regulator



2 Sheets-Sheet 1 Filed March 3l, 1955 INVENTOR. W/LL/AM G, /VE/LDATTORNEY Feb. 4; 195s Filed March 3l, 1955 W. G. NEILD CARBON PILEREGULATOR 2 Sheets-Sheet 2 I Il I I l I I o ARMATURE lMVEMENT IINVENTOR. WML/AM G /I/E/LD A TTORAF Y nted States Patent @thee 2,822,452riatented Feb. 4, 1958 CARBON PILE REGULATOR William G. Neild, FairHaven,

Aviation Corporation, of Delaware Application March 31, 1955, Serial No.498,272

1 Claim. (Cl. 201-51) N. J., assigner to Bendix Eatontown, N. J., acorporation The present invention relates to electrical regulators andmore particularly to carbon pile type regulators.

Heretofore, carbon pile regulators have been limited by the resistancerange of the pile and by the wattage dissipation. ln order to secure thehigher resistance necessary for operation under some conditions, thelower c actuating system. A new combined carbon pile is provided thathas the desirable high resistance advantage of the high resistance pileand the low resistance advantage of the lower resistance carbon pile,thus greatly extending the range of the regulator'.

In addition to extending the resistance range, there is a gain in thewattage dissipating capacity of the regulator. Past experience indicatesthat beyond `a certain pile length there is very little gain in the heatdissipating ability of the regulator due to the tendency of the carbonpile to pack at the xed end. By using the two carbon piles, when maximumwattage exists, both piles `combine to dissipate the heat. While the lowresistance pile dissipates the greater percentage of the total watts,the dissipation will be less than that of a same total wattagecondition. Hence, the double pile regulator can be rated up in watts andstill not exceed the maximum permissible `carbon pile temperatures.

it is an object of the invention to provide an improved carbon pileregulator.

Another object of the invention is to provide a novel carbon pileregulator having a wide resistance range.

Another object of the invention is to provide a novel regulator capableof going from a relatively low resistance value to a relatively highresistance value.

Another object of the invention is to provide a novel regulator withimproved wattage dissipation.

Another object of the invention is to provide a regulator with improvedwattage and resistance characterrstics.

The `above and other objects and features of the invention will appearmore fully hereinafter from a 4consideration of the followingdescription taken in connection with the accompanying drawings whereinone embodiment of the invention is illustrated by way of example.

In the drawings:

Figure l is a cutaway view of a regulator embodying the invention.

Figure 2 is a schematic embodying the invention.

Figure 3 is a graph illustrating the principle of the invention.

diagram of a regulator system single pile under the Reference is nowmade to Figure 1 of the drawing wherein a carbon pile regulator isindicated generally by the numeral ti. The regulator 5 has anelectromagnetic coil 6, armature assembly 7, low resistance carbon pile8 and high resistance carbon pile 9. The coil 6 is surrounded by acasing lil of a suitable ferromagnetic material. The casing 1d has aflange Sti extending inward and forming the pole face for theelectromagnetic assembly. A bottom plate 12 is secured to the casing it)by screws 13 or in `any other suitable manner. A core member 14 of asuitable ferromagnetic material is screv-threaded to the plate 12 andprojects into the coil 6.

A carbon pile housing 15 having heat radiating tins 16 is secured to thecasing 1d by post 17. The housing 15 has a plate i8 formed integraltherewith and a counterbore portion 19. Mounted in the housing 1S andextending longitudinaliy therein are tubes 19A and 20 of a suitablenon-conducting material. The tube 19A carries carbon disc 2l forming thecarbon pile 8 and the tube 2d carries carbon disc 22 forming the carbonpile i?. Cap members 23 and 2.4i having threaded portions 25 and 2eadapted to receive pile adjusting screws 27 and 255 are insulated fromthe plate i8 by insulating member 29 and secured thereto by screws 3d.The carbon pile is carried between contact plugs 31 and 32. The carbonpile 9 is carried in like manner between conduit plugs 33 and 34.

The armature assembly 7 has a diaphragm type spring 35 seated on member11 of the housing 1d. An armature plate 36 is positioned on the side ofthe spring 35 adjacent to the core i4. On the opposite side of thespring 35, a clamping plate 37 is positioned so that the spring 35 isclamped between the plates 36 and 37 by suitable fastening screws 3d.Cup-shaped members 39 and 4d, adapted to hold contact plugs 3i and 33,respectively, are mounted on the plate 37 by screws or other suitablemeans. An insulating member il insulates the members 39 and 46 from theplate 37. The armature plate 36 comprises a ring-like section 42 securedby the screws 38 and a center section 43. The sections ft2 and i3 areadapted to be screw-threaded together.

A member afi is secured to the clamping plate 37 by screws (not shown).Secured to the member 44 by screws 45 is a counterbalance 46. One sideof a spring-like member 47 is clamped between the member 44 andcounterbalance 56. The other side of the member 47 is secured to thecasing 1% by clamping member 48 and screws 49. An opening 5d is providedin the housing 15 for the member dfi.

Reference is now made to Figures 2 and 3 of the drawing for anexplanation or" the operation of the invention. in Figure 2 theregulator 5 is illustrated diagrammatically in a generator systemwherein corresponding parte have been assigned the same referencenumerals as in Figure 1.

A generator is indicated generally by the numeral 51 and has an armature52, series eld winding 53, and shunt eld winding 54. One terminal of thearmature 52 is connected to load bus 55 The other terminal of armature52 is connected through the series lield winding to load bus Sie. Oneend of the shunt field winding 54. is connected by conductor S7 to thebus 55. The other end of the winding S is connected by conductor 58 toone end of the carbon piles 3 and 9 of the regulator 5. The other end ofthe carbon piles 8 and 9 are connected by a conductor 59 to the bus 55.

The regulator 5 is shown diagrammatically herein as including thearmature 36 pivoted at 47 and biased by the spring 35 in a direction fordecreasing the resistance of the carbon piles 3 and 9. Opposing thespring 35 is the electromagnetic control winding 6. One end of the 3Winding 6 is connected by a conductor 60 to the bus 55. The other end ofthe winding 6 is connected by a conductor 61 to the bus S6. A variableresistance 62 may be inserted in the conductor 6G to regulate thevoltage setting of the windings.

The resistance and elongation characteristics of a carbon pile aredetermined by the number of carbon discs and their thickness. A pilemade up of many thin discs will have a higher resisitance and greaterelongation than one of the same length made up of a few thick discs. Byproper selection of the disc, carbon piles may be made up having theresistance characteristics illustrated by the Hi and Lo curves of Figure3, wherein resistance is plotted as a function of armature movement.

The two carbon piles 8 and 9 are actuated by the common armature 36 andare electrically connected in parallel, The high resistance pile 9 has agreater elongation than the low resistance pile 8. From the curves ofFigure 3, it can be seen that at the high speed no load condition, orhigh resistance condition, only the high resistance pile is in thecircuit and the low resistance pile is open. As the total resistance ofthe regulator is decreased, the low resistance pile makes contact andenters into the circuit. The resultant resistance characteristics of thetwo piles in parallel are shown by the dashed line curve. As theregulator resistance decreases, the low resistance pile picks up moreand more of the load andV at the low speed, full load condition, it iscarrying most of the load. Although the low resistance pile opens as theregulator resistance increases, it is in parallel with the highresistance pile, hence it always has a resistance connected across it,therefore, never breaks an inductive 4 load. Thus, any arcs drawn in thelow resistance pile will be of very low wattage, non-inductive and hencenot destructive.

Thus, it can be seen that a regulator, such as described herein, wouldhave a longer life in that the high resistance carbon pile would breakall the transient arcs, while the low resistance carbon pile would dothe bulk of the regulating. Further, the transition from one pile to theother is gradual and there is no abrupt break,

Although only one embodiment of the invention has been illustrated anddescribed, various changes in the form and relative arrangement of theparts, which will now appear to those skilled in the art, may be madewithout departing from the scope of the invention.

What is claimed is:

An electric regulator comprising a housing, a first plurality ofcompressible carbon discs forming a first carbon pile having oneresistance characteristic, a second plurality of compressible carbondiscs forming a second carbon pile having a different resistancecharacteristic, an armature operably connected so as to adustablycornpress said carbon piles, a diaphragm type spring for biasing saidarmature in a first direction, and electromagnet for biasing said'armature in the opposite direction in opposition to said spring, andmeans connecting said carbon piles in parallel whereby a thirdresistance characteristic is obtained.

Donop Oct. 28, 1919 Turbayne Nov. 4, 1919

